Fluid pump assembly

ABSTRACT

A fluid transfer pump assembly that includes a motor enclosure assembly that forms a motor cavity sized to receive a motor. The motor enclosure includes a flame path that extends from an interior joint to an exterior joint. The interior joint faces the motor cavity and the exterior joint faces exterior of the motor enclosure assembly. A heat sink is located in the motor cavity of the motor enclosure assembly. A portion of the heat sink abuts the interior joint.

RELATED APPLICATIONS

The present application is a continuation of application Ser. No.15/958,217 filed on Apr. 20, 2018 entitled Fluid Pump Assembly. Thesubject matter disclosed in that provisional application is herebyexpressly incorporated into the present application in its entirety.

TECHNICAL FIELD AND SUMMARY

The present disclosure is related to fluid transfer pump assemblies, andparticularly to such pump assemblies that have heat dissipation, statusfeedback signals, and switching functionality in explosion-proof motorenclosure environments.

Fluid transfer pumps move fluid from one location to another. Oneexample includes a pump that moves hazardous fluid such as gasoline froma storage tank to a vehicle. The pump may employ vanes, diaphragms, orother like structures that are rotated or oscillated inside the pump viasome motive force such as an electric motor. The vanes are located in apump enclosure that is in fluid communication with inlet and outletmanifolds. The inlet manifold may also be in communication with thegasoline in the storage tank while the outlet manifold may also beattached to a hose or other structure configured to deliver the gasolineto another location. As the motor rotates the vanes, a vacuum is createdin the pump enclosure to cause the gasoline already present in the tankto be drawn up through the inlet manifold. The vanes then rapidly pushthe gasoline out through the outlet manifold and the hose, to bedelivered to the other location. A nozzle or other type of valvestructure may be attached at the other end of the hose to selectivelydispense the pumped gasoline.

An electric motor is a suitable means for rotating the vanes inside thepump. The motor is also able to generate enough rotational velocity toeffectively draw up and dispense the fluid at a sufficient rate.

Fluids like gasoline, however, may pose a risk when utilizing electricmotors since such motors have a propensity to produce heat, sparks andarcs, and even flames during abnormal conditions. Placing such motors inpotentially flammable environments can, therefore, be hazardous. That iswhy electric motors are housed in explosion-proof enclosures. Theseenclosures prevent any internal explosion from propagating to asurrounding explosive atmosphere.

One manner of mitigating explosions that occur inside the motorenclosure from propagating to outside the motor enclosure is to providea flame path at the joint between the motor enclosure and end bell. Theflame path may be an extended seam located at the motor enclosure jointwhere the motor enclosure and end bell couple to each other.Illustratively, the end bell may include an extended flange sized to fitagainst an elongated collar on the motor enclosure. The result is apathway located between the spaced-apart interior and exterior seams ofthe enclosure and end bell. The space between the extended flange andcollar provides a pathway that will extinguish any flames generated byan explosion inside the enclosure. This prevents the explosion fromreaching the external explosive environment thereby eliminating risk ofigniting any flammable concentration of vapors outside of the enclosure.

As the skilled artisan will appreciate, creating these flame paths addsexpense and complexity to the motor enclosure and, thus, the pump as awhole. Further exacerbating the issue is if any additional ports oropenings are needed. In these instances another flame path will beneeded for each additional opening. In other words, more openings in themotor enclosure means more flame paths which means more cost.

Illustrative embodiments of this present disclosure provide multiplesolutions for operating and enhancing the fluid pump motor locatedinside the explosion-proof motor enclosure, but without needingadditional openings requiring additional flame paths, and, thus,additional costs.

An illustrative embodiment of the present disclosure includes anexplosion-proof motor enclosure that comprises a heat sink forefficiently transferring heat generated by components located within theenclosure, but without requiring openings in the enclosure. Anotherillustrative embodiment of the present disclosure comprises a statusfeedback signal system that conveys operating conditions of the motor,again, without requiring additional openings extend through the motorenclosure. Another illustrative embodiment of the present disclosureprovides a switch system to activate and deactivate the electric motor.And yet again, this is accomplished without requiring additionalopenings in the motor enclosure.

Another illustrative embodiment of the present disclosure provides afluid transfer pump assembly comprising: a motor enclosure assemblyformed by a motor enclosure and an end bell; wherein the motor enclosureand the end bell join together to form a motor cavity sized to receive amotor; wherein the motor enclosure includes a collar that extends fromthe motor enclosure at a collar base, encircles a portion of the motorcavity, and terminates at a collar end distal from the collar base;wherein the collar includes a collar surface; wherein the end bellincludes a flange that extends from the end bell at a flange base,encircles a portion of the motor cavity, and terminates at a flange enddistal from the flange base; wherein the flange includes a flangesurface; wherein when the motor enclosure and the end bell are joinedtogether to form the motor cavity the collar surface faces the flangesurface to form a flame path between the collar and flange surfaces;wherein when the motor enclosure and the end bell are joined together toform the motor cavity the collar base is located adjacent the flange endto form an interior-only joint that faces the motor cavity but notlocated exterior of the motor enclosure assembly; wherein when the motorenclosure and the end bell are joined together to form the motor cavitythe flange base is located adjacent the collar end to form anexterior-only joint that is located exterior of the motor cavity butdoes not face the motor cavity; wherein the flame path extends from theinterior-only joint to the exterior-only joint; a heat sink composed ofa panel positionable at the interior-only joint of the motor enclosureassembly; wherein the panel of the heat sink has a first surface, aperimeter surface, and a second surface such that the second surface islocated adjacent the perimeter surface and opposite the first surface;and a heat generating power conversion circuit board that is attachableto the panel of the heat sink at a location selected from the groupconsisting of the first surface and the second surface; wherein aportion of the first surface of the panel of the heat sink abuts thecollar base at the interior-only joint; wherein a portion of the secondsurface of the panel of the heat sink abuts the flange end at theinterior-only joint; and wherein the perimeter surface of the panel ofthe heat sink does not interfere with the flame path extending from theinterior-only joint to the exterior-only joint of the motor enclosureassembly.

In the above and other illustrative embodiments, the fluid transfer pumpassembly may further comprise: the motor cavity being cylindrical, thecollar surface of the motor enclosure being cylindrical, and the flangesurface of the end bell being cylindrical; the panel of the heat sinkhaving a circular shape such that the end surface of the panel of theheat sink is located adjacent the cylindrical collar surface of themotor enclosure; the panel of the heat sink is located only interior ofthe motor enclosure assembly wherein no portion of the heat sink extendsexterior of the motor enclosure assembly, and wherein no vents in themotor enclosure assembly are configured to dissipate heat from theheat-generating power conversion circuit board; a pump enclosureattached to the motor enclosure assembly; and the motor enclosure andend bell are both made of a heat-conducting material.

Another illustrative embodiment of the present disclosure provides afluid transfer pump assembly comprising: a motor enclosure assembly thatforms a motor cavity sized to receive a motor; wherein the motorenclosure includes a flame path composed of a pathway formed by twofacing surfaces of the motor enclosure; wherein the pathway is formed bythe two facing surfaces of the motor enclosure that extend from aninterior joint to an exterior joint; wherein the interior joint facesthe motor cavity and the exterior joint faces exterior of the motorenclosure assembly; and a heat sink located in the motor cavity of themotor enclosure assembly; wherein a portion of the heat sink abuts theinterior joint; and wherein the heat sink does not interfere with theflame path extending from the interior joint to the exterior joint ofthe motor enclosure assembly.

In the above and other illustrative embodiments, the fluid transfer pumpassembly may further comprise: the motor enclosure assembly beingcomposed of a first motor enclosure portion and a second motor enclosureportion; the first motor enclosure portion includes a first facingsurface of the two facing surfaces, and the second motor enclosureportion includes a second facing surface of the two facing surfaces; theinterior joint includes a first joint surface of the first motorenclosure portion and a second joint surface of the second motorenclosure surface; the portion of the heat sink that abuts the interiorjoint contacts both the first and second joint surfaces such that heatin the heat sink transfers to the first and second motor enclosureportions; the interior joint encircles the motor cavity, across-sectional profile of the motor cavity is circular, square, oval,quadrilateral, and polygonal; the first and second motor enclosureportions are separable; the portion of the heat sink that abuts theinterior joint includes a periphery that extends about the perimeter ofthe heat sink; the periphery abuts the interior joint of the motorenclosure assembly; a heat generating power conversion circuit board isattachable to the heat sink and transfers heat to the heat sink.

Another illustrative embodiment of the present disclosure provides afluid transfer pump assembly comprising: a motor enclosure assembly thatforms a motor cavity sized to receive a motor; wherein the motorenclosure includes a flame path; wherein the flame path extends from aninterior joint to an exterior joint; wherein the interior joint facesthe motor cavity and the exterior joint faces exterior of the motorenclosure assembly; and a heat sink located in the motor cavity of themotor enclosure assembly; wherein a portion of the heat sink abuts theinterior joint; and wherein no portion of the heat sink extends exteriorto the motor enclosure assembly.

In the above and other illustrative embodiments, the fluid transfer pumpassembly may further comprise: the heat sink does not interfere with theflame path that extends from the interior joint to the exterior joint;the motor cavity including a motor controller that supplies power to amotor having a rotor and a stator, wherein the stator includes aplurality of pole pairs of wire windings that create a movingelectromagnetic force to rotate the rotor, wherein the motor controllerupon receiving signals of a condition of the motor, directs current toat least one pole pair of wire windings at a voltage that does not causethe motor to rotate, but causes the at least one pole pair of wirewindings to vibrate to create a status feedback signal; and the motorcavity includes a switch assembly that comprises at least one magnetlocated on a shield extending transverse from that magnet, a switchactuator located adjacent to the shield opposite the at least onemagnet, wherein the switch is engageable with the magnet through theshield such that as the switch actuator moves the magnet moves, whereinthe magnet fits into a space on the motor enclosure that is spaced apartfrom the motor cavity in the motor enclosure, a magnetic field sensorlocated inside the motor cavity of the motor enclosure assembly andisolated from exterior of the motor enclosure cavity, wherein themagnetic field sensor is in electric communication with a motorcontroller to selectively supply current to the motor to operate same,wherein the magnetic field sensor produces a signal when it detects amagnetic field of a predefined characteristic generated by the magnet.Illustratively, the motor controller interprets the signal generated bythe magnetic field sensor and acts to switch on/off based on predefinedparameters.

Additional features and advantages of the fluid transfer pump assemblywill become apparent to those skilled in the art upon consideration ofthe following detailed descriptions exemplifying the best mode ofcarrying out the fluid transfer pump assembly as presently perceived.

BRIEF DESCRIPTION OF THE DRAWINGS

The concepts described in the present disclosure are illustrated by wayof example and not by way of limitation in the accompanying figures. Forsimplicity and clarity of illustration, elements illustrated in thefigures are not necessarily drawn to scale. For example, the dimensionsof some elements may be exaggerated relative to other elements forclarity. Further, where considered appropriate, reference labels may berepeated among the figures to indicate corresponding or analogouselements.

FIG. 1 is a front perspective view of a fluid pump assembly according toan illustrative embodiment of the present disclosure;

FIG. 2 is a reverse perspective view of the fluid pump assembly;

FIG. 3 is a perspective exploded view of the motor enclosure and rearend bell portions, along with selected components to be containedwithin;

FIG. 4 is a side cross-sectional view of the motor enclosure attached tothe rear end bell;

FIG. 5 is a perspective view of the motor enclosure, rear end bell, andpump enclosure portions of the fluid pump assembly;

FIG. 6 is an exploded view of the motor enclosure and rear end bell;

FIG. 7 is a perspective exploded detail view of the switch assembly,motor enclosure, and motor controller board components of the fluidtransfer pump assembly;

FIG. 8 is a top downward looking cross-sectional view of a portion ofthe fluid transfer pump assembly; and

FIGS. 9A and 9B are side cross-sectional views of the motor enclosureand switch mechanism.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplification set out hereinillustrates an embodiment of the fluid transfer pump assembly, in oneform, and such exemplification is not to be construed as limiting thescope of the fluid transfer pump assembly in any manner.

DETAILED DESCRIPTION OF THE DRAWINGS

The figures and descriptions provided herein may have been simplified toillustrate aspects that are relevant for a clear understanding of theherein described devices, systems, and methods, while eliminating, forthe purpose of clarity, other aspects that may be found in typicaldevices, systems, and methods. Those of ordinary skill may recognizethat other elements and/or operations may be desirable and/or necessaryto implement the devices, systems, and methods described herein. Becausesuch elements and operations are well known in the art, and because theydo not facilitate a better understanding of the present disclosure, adiscussion of such elements and operations may not be provided herein.However, the present disclosure is deemed to inherently include all suchelements, variations, and modifications to the described aspects thatwould be known to those of ordinary skill in the art.

A front perspective view of illustrative pump assembly 2 is shown inFIG. 1. As shown, fluid transfer pump 2 includes a motor enclosure 4,rear end bell 6, switch mechanism 8, pump enclosure 10, and manifolds12. Motor enclosure 4 is part of an explosion-proof enclosure along withend bell 6 and pump enclosure 10 which prevents any sparks, arcs, andflames, from exiting the motor enclosure 4, rear end bell 6, and pumpenclosure 10. Switch mechanism 8, which will be discussed in furtherdetail with respect to FIGS. 7 through 9, is illustratively positionedon the exterior of motor enclosure 4 as shown. In the illustratedembodiment, switch mechanism 8 is shown having a switch shaft assembly14 attached to switch lever arm 16 via fastener 18. Illustratively, aswitch lever handle 20 attached to switch lever arm 16 assists inoperating switch mechanism 8. Further, locking portion 22 allowspadlocks or other securing structures to secure the nozzle to the pump(not shown). Also shown is a nozzle hanger mount 24. It will beappreciated by the skilled artisan that fluid transfer pump 2 may beconfigured to pump gasoline or other like hazardous materials in asimilar manner to conventional gas station pumps. Particularly, gasdispensing nozzles (not shown) may be employed with the fluid transferpump 2 and operate in a similar method as their gas station fuel pumpnozzle counterpart.

Also shown in this view is pump enclosure 10 located adjacent motorenclosure 4 and capped with a rotor cover 26 via fasteners 28. In thisillustrative embodiment, pump enclosure 10 encloses a rotor and vanesthat are rotated by an electric motor located in motor enclosure 4. Therotating vanes to draw up and expel fluid from inlet manifold portion 30and out through outlet manifold portion 32. Also shown are aestheticjoint covers 34 and 36. These covers illustratively shroud theexplosion-proof joints that exist between motor enclosure 4 and rear endbell 6, as well as motor enclosure 4 and pump enclosure 10.

A reverse perspective view of fluid transfer pump 2 is shown in FIG. 2.This view also shows motor enclosure 4, rear end bell 6, pump enclosure10, and manifold 12. Particularly depicted is the power supply port 42through which a power cord enters to connect the power converter inmotor enclosure 4 with an exterior power supply, such as a vehiclebattery, AC mains, etc.

It will be appreciated by the skilled artisan upon reading thisdisclosure that the primary components that make up the exterior body offluid transfer pump 2 are the motor enclosure 4, rear end bell 6, andpump enclosure 10. Manifold 12 is indeed part of pump enclosure 10. Itis further appreciated that rear end bell 6 and pump enclosure 10 may beattached to motor enclosure 4 via fasteners such as fastener 44 asshown. It is appreciated, however, that other attaching or fasteningmeans may be employed with the pump so long as the explosion-proofcharacteristics, as known in the relevant art, are not compromised byattaching the structures together. An important, albeit known, featureof fluid transfer pumps of the type like fluid transfer pump 2 is thatit is specifically designed so that the motor located inside motorenclosure 4 will not produce any flame or explosion that can propagateoutside of motor enclosure 4. A conventional way of achieving this is tomake sure a flame path exists at each motor enclosure opening.

And illustrative embodiment of the present disclosure providesexplosion-proof containment between motor enclosure 4 and rear end bell6. More specifically, an illustrative embodiment of the presentdisclosure provides a heat sink mechanism within motor enclosure 4 andrear end bell 6 that is capable of dissipating heat while not requiringadditional openings in either the motor enclosure 4 or rear end bell 6that would require adding more flame paths. In this illustrativeembodiment, it is contemplated that the motor for use in this pump maybe a brushless motor requiring a power converter.

For pumps such as these, they may be powered through battery power. Thismeans 12-24 volts can be supplied to the pump. With new motortechnology, particularly with brushless-type motors, it may be necessaryto boost the 12-24 volts up to 120 volts direct current. Accordingly,this may require a two stage power converter to supply the needed powerto the motor. A consequence of this power conversion, however, is asubstantial increase in heat on the circuit boards located insideenclosure 4.

Dissipating heat from motor components and circuit boards is known. Fansand venting are common means of pulling heat generated by such boardsaway from the motor. In an explosion-proof motor enclosure environment,fans and venting are not really options, however. Again, how motorenclosures are made explosion-proof is by their ability to extinguishany flames generated by an explosion inside the enclosure through thesenarrow flame paths located at the joints between connecting enclosurecomponents. Having fans and vents, not only add to the complexity of thepump assembly as a whole, but they end up defeating the ability of motorenclosure 4 to be explosion-proof. In the motor enclosures of thepresent disclosure (such as motor enclosure 4 with end bell 6) it iseven more difficult to create heat dissipation without vents.

Accordingly, illustrative embodiment of this present disclosure providesa heat sink system that can transfer heat from the power conversioncircuit board (or other structures) away from the internal structures ina motor enclosure without the use of any fans or venting. In anillustrative embodiment, a heat sink plate may be placed in contact withthe circuit board or any other structure that produces heat needing tobe removed. The heat sink may be fitted between the interior jointportion of the motor enclosure and the interior joint portion of therear end bell. In this configuration, the plate is in contact with otherheat transfer materials (i.e., metal structures) on opposite sides ofthe heat sink. This metal to metal contact between the heat sink andboth the motor enclosure and rear end bell gives increased surface areacontact between structures which allows more heat to dissipate. Inaddition, having the heat sink sandwiched between the interior joint ofthe flame path of the enclosure means the heat sink has face-to-facecontact for effective heat distribution while at the same time notinterfering with the flame path structures or require any venting orfans.

A perspective exploded view of motor enclosure 4 and rear end bell 6with selected components to be contained within are shown in FIG. 3.Here, a power conversion circuit board 46, heat sink, 48, and plugassembly 50 are shown to be contained within cavity 52 of motorenclosure 4. Also shown in this view is collar 54 that includes an innerperiphery that forms a flame path surface 56. Likewise, extending fromrear end bell 6 is flange 58 that includes its flame path surface 60that will be positioned adjacent flame path surface 56 of collar 54. Aledge 62 is formed at the edge of flame path surface 56 and cavity 52 ofmotor enclosure 4 to serve as an interior joint (see FIG. 4) and acontact surface for heat sink 48. This provides the connection betweenthe two for efficiently transferring heat from heat sink 48, into andthrough motor enclosure 4 and rear end bell 6.

A side cross-sectional view of motor enclosure 4 attached to rear endbell 6 as shown in FIG. 4. This view depicts how heat sink 48 is able totransfer heat that is generated by power conversion circuit board 46 toboth motor enclosure 4 and rear end bell 6. As shown, power conversioncircuit board 46 is attached to surface 66 of heat sink 48. Thissubstantial contact between the two structures means the heat generatedby power conversion circuit board 46 (from power loss during theconversion process) may be effectively transferred into the metal bodyof heat sink 48. Second surface 68 of heat sink 48 is in contact withledge 62 interior of motor enclosure 4. The contact between these twosurfaces allow the heat that is transferred from power conversioncircuit board 46 and into heat sink 48 via first surface 66 to furthertransfer through contact between ledge 62 and second surface 68 into theheat conductive body 70 of motor enclosure 4. This provides a continuouspath for heat to transfer and dissipate through motor enclosure 4. Atthe same time, first surface 66 of heat sink 48 also engages edge 72,located at the periphery of flange 58 of rear end bell 6. Because rearend bell 6 may also be made of a heat conducting material, the directcontact between edge 72 and first surface 66 provides a second pathwayto transfer heat away from power conversion circuit board 46 and throughheat sink 48 to rear end bell 6. Furthermore, the contact between heatsink 48, motor enclosure 4 and rear end bell 6 extends the circumferenceof those structures in cavity 52. Accordingly, heat sink 48 has theavailability of all the heat transfer material embodied in both motorenclosure 4 and rear end bell 6 to transfer the heat generated by powerconversion circuit board 46.

At the same time, it is notable that heat sink 48 does not interferewith flame path 64 located at the connection of motor enclosure 4 andrear end bell 6. Flame path surfaces 56 and 60 still operate as normalwith interior joint 74 still available to receive any combustion despitethe presence of heat sink 48 and can extinguish any combustion beforereaching exterior joint 76. Accordingly, this configuration allows heatsink 48 to exploit the heat conductive materials of both motor enclosure4 and heat sink 6 without any need for fans or venting. Thisconfiguration also allows the flame path between those two structures tooperate as normal. It is notable that a seam still exists between ledge62 and second surface 68 of heat sink 48 as well as perimeter surface 78of heat sink 48 and flame path surface 56 of collar portion 54 of motorenclosure 4. This means any ignition that occurs within cavity 52, itcan still exit between ledge 62, and second surface 68 and travelbetween perimeter surface 78, flame path surface 60 and flame pathsurface 56 before reaching exterior joint 76.

Another illustrative embodiment of the present disclosure is directed toa motor status feedback signal generating system. This system generatesstatus feedback tones within the motor located inside the motorenclosure to convey particular operating conditions of the motor. Acircuit board such as circuit board 46 discussed with respect the priorembodiment may include a motor controller. It is appreciated that thestatus feedback signal may be audible or imperceptible. In anillustrative embodiment, the motor status feedback signal generatingsystem may produce an audio signal that is imperceptible to a human butcan be detected by a microphone and processed by a device such as acomputer or smart phone to convey the motor status.

The motor controller includes a microprocessor that operates the motor.In other words, the motor controller causes the rotor to rotate. Astator surrounds the rotor and includes a series of opposing pairs ofwindings. Current is run through these opposing pairs of windings in aconcentric manner to create a moving electromagnetic force. A magnet onthe rotor is attracted to that moving electromagnetic force. Whenopposing pairs of windings that surround the rotor are energized in asequence one after another, they create the moving electromagnetic forcearound a circle. The magnet on the rotor being attracted to theelectromagnetic force chases the moving electromagnetic force therebycausing the rotor to rotate. By increasing or decreasing the amount ofcurrent that goes into the windings as well as the rate of the sequence,the motor controller may control the motor's speed.

In the context of a hazardous fluid pump, it is necessary to have anexplosion-proof enclosure for the motor to prevent any combustion thatoccurs within the motor enclosure from causing an explosion exterior ofthe enclosure. And in order to accomplish this, any openings or jointsmust have a flame path to extinguish any combustion that occurs withinthe motor enclosure before it can reach exterior of the motor enclosure.This, as previously discussed, adds complexity and cost to the motorenclosure. It can therefore be necessary to have only a minimum numberof openings needed in the motor enclosure to operate the motor. In thecase of pump 2, the openings may be limited to the power supply (e.g.,power cord) and the motor shaft (not shown). All of the other componentsof the motor including the motor controller, stator, windings, and anyother structural or electronic components are contained within the motorenclosure.

In addition to operating the motor, the motor controller has thecapability to monitor the functions of the motor to ensure that it isoperating properly, and if not, diagnose the problem. This capability isnot uncommon to motor controllers. A motor controller can detect faultconditions with a motor such as over or under voltages, hightemperatures, application faults, battery fault, etc. The problem withinthe context of an explosion-proof motor enclosure is attempting toconvey those diagnosed faults to the operator. Using audiovisualindicators such as displays, lights, or external speakers, all requirewires to be sent out through the motor enclosure between the motor andthe outside environment. To do this requires additional complexity andexpense to the pump. This is because an additional flame path will haveto be created for each opening. Creating the additional needed flamepath may be difficult just to accommodate these wires.

Accordingly, an illustrative embodiment of the present disclosureprovides a means for creating an alert scheme to convey operating statusof the motor inside the explosion-proof motor enclosure without havingto extend any wires or components from the interior to the exterior ofthe motor enclosure. In this illustrative embodiment, the motor itselfmay be employed by the motor controller to generate status feedbacksignals that are perceptible exterior of the motor enclosure and canindicate different status alerts about the motor or application.Allowing the operator to receive feedback without the need to createadditional flame paths in the motor enclosure allows for simplerconstruction while providing enhanced operation of the pump.

A perspective view of motor enclosure 4 with rear end bell 6 and pump 2is shown in FIG. 5. This view demonstrates an explosion-proof pumpenclosure where there are no openings. Specifically, motor enclosure 4and rear end bell 6 do not extend any wires or other structures exteriorof same to provide operational feedback to the operator exterior of pump2. In other words, the motor and its attendant structures are allisolated within motor enclosure 4 while generating status signals thatcan be perceived exterior of pump 2.

An exploded view of motor enclosure 4 and rear end bell 6 is shown inFIG. 6. This view also depicts motor stator portion 80 and motorcontroller 82. Motor stator portion 80 and motor controller 82 areconfigured to fit into cavity 52 of motor enclosure 4. This view alongwith the view of FIG. 5 allows the skilled artisan to appreciate howmotor stator portion 80 and motor controller 82 are isolated fromexterior of pump 2.

As previously identified, how motor controller 82 operates motor 80 isby supplying current in a sequential fashion to winding pairs thatsurround the rotor on the stator. To accomplish this, however, requiresspecific modulated voltages in sequence around the coils of the stator.That said, if the voltage is not sufficient or is sequenced around thestator wire windings improperly, the rotor will not turn. Changing thefrequency of the wave form of the current supplied to the motor althoughnot being sufficient to cause the rotor to rotate, will cause theopposing pairs of wires of the stator to vibrate, not unlike piano orguitar wires. The effect of this is a status feedback signal beinggenerated by the motor itself. For example, a motor including motorstator portion 80 in motor enclosure 4 may operate at a PWM (pulse widthmodulation) frequency of 15,000 hertz. In other words, supplying currentto the opposed windings in the stator in a rotational sequence at arotational frequency of 120 hertz will cause the rotor in the motor tospin and operate the pump. But if 1,500 hertz is supplied to the opposedwindings, the rotor will not rotate but will only cause the wires tovibrate producing the status feedback signal.

While the motor is running, the motor controller continuously runsinterrupt service routine (ISR) loops to check the status of the motor.If the routine detects a fault preventing the motor 80 from operatingproperly, motor controller 82 can send an appropriate frequency signalto one or more of the opposed windings on the stator to cause them tovibrate. That resulting status feedback signal will be perceptible bythe operator to indicate there is a fault with the motor or application.In addition, the frequency and duration of the vibrating wires may bechanged so each of the several varieties of faults can each be assigneda unique tone or tone sequence to convey to the operator the precisetype of fault that is occurring with the motor. For example, if anexcess temperature fault is detected, motor controller 82 can send anappropriate signal frequency to the motor windings for a period of time,illustratively 0.3 seconds, stop the tone for a second period of time,for example 0.2 seconds, and then repeat. In an almost Morse-code-likefashion, the particular pitch of the tones and durations of same mayindicate to the operator that there is a specific fault—such as a hightemperature fault. If there is a low battery fault detected, motorcontroller 82 may produce a unique sequence of tones. These tones mayalso last for different durations and intervals that will be unique tothat specific fault. By hearing this sequence of tone, the operator willknow there is a low battery fault.

In an illustrative embodiment, tones are employed to indicate faultconditions. Distinguishing tones may be created by changing the pitchand the number of tones per fault. For example,“application/installation” and “hardware” faults may be identified bysets of tones that are distinguishable by different ordered combinationsof high or low pitches. In the illustrative embodiment, the followingTables I and II depict several potential pump, motor, or applicationfault conditions. The Tables are divided between“application/installation faults” and “hardware faults.” The three-toneTable lists “application/installation” faults that identify installationissues related to the pump such as priming or supply voltage, forexample. The four-tone Table indicates “hardware” faults which identifyconditions outside the operating parameters of the pump such as hardwareand motor overtemperatures. As shown in both Tables below, an up arrow“↑” means high tone and a down arrow “↓” means low tone. Illustratively,the tone arrangements may be predetermined so the user will know whichfault condition is indicated by listening to the tones generated by themotor inside the enclosure.

TABLE I Three-Tone Faults (Application/Installation Faults) TonesCondition ↑↓↓ Low battery voltage (auto shut-off) ↑↓↑ High batteryvoltage (auto shut-off) ↓↑↑ Locked rotor (auto shut-off) ↓↑↓Priming/Suction/Lift failure

TABLE II 4-Tone Faults (Hardware faults) Tones Condition ↓↑↑↑ Hardwarefault (auto shut-off) ↓↑↓↓ Hardware overtemperature (auto shut-off) ↓↓↑↑Motor overtemperature (auto shut- off) ↓↓↑↓ Motor overvoltage (autoshut-off) ↓↓↓↑ Motor undervoltage (auto shut-off)

In Table I, the difference between a low battery voltage fault and ahigh battery voltage fault is the former is indicated by a three tonesignal composed of one high tone and then two successive low tones. Incontrast, the high battery voltage fault has a signal that is one hightone, one low tone, and then a high again. For the hardware faults inTable II, a hardware overtemperature fault may include four tonescomposed of one low tone, one high tone, and then two succeeding lowtones. In contrast, a motor overtemperature fault may be composed of twolow tones followed by two successive high tones. It will be appreciatedby the skilled artisan that any combination of status feedback signalsequences may be used to identify any variety of faults.

By employing precise status feedback signal sequences, not only can thefault types be identified by the operator, but they can also be conveyedto a remote entity. For example, a digital audio recorder, telephone, orphone app may be used to record the sounds and send them to technicalsupport to further diagnose and/or suggest repair options.

Another illustrative embodiment of the present disclosure provides aswitch assembly that activates and deactivates the pump motor butwithout any physical contact with the motor or motor controller. Asdiscussed previously, adding more openings in an explosion proof motorenclosure requires flame paths and special design considerations thatadd complexity and cost to the pump. Because of this, the fewer openingsin the explosion-proof motor enclosure there are the simpler the pumpconstruction and hence, the less expensive it is to manufacture.Typically, many pumps, particularly those dispensing fuels, include apivoting lever where rotation in one direction activates the pump, androtation in the reverse direction deactivates the pump.

An illustrative embodiment of the present disclosure includes an on andoff switch for the pump motor that is part of the lever, but not part ofthe motor controller that activates the motor. No part of the switchcomes into physical contact with any component of the motor through themotor enclosure. Instead, the switch includes a magnet or magnets thatremain exterior of the motor enclosure but are detectible by a magneticsensor located inside the motor enclosure. The magnets create a magneticfield that passes through the material of the motor enclosure (typicallyaluminum) and is readable by the sensor inside the enclosure. The sensoritself is in electric communication with the motor controller so thatwhen a magnetic field having particular characteristics is detected bythe sensor, it will send a signal to the motor controller to eitheractivate or deactivate the motor. This is all accomplished without anypart of the switch physically extending through the motor enclosure walland contacting the components inside.

Another aspect of an illustrative embodiment of the present disclosureincludes the lever assembly having a switch lever mount that may be madeof steel, iron, or other like material. This lever mount serves as ashield for the magnet to prevent any operational interference ordeliberate attempts to create an alternate magnetic field in order toactivate the sensor in the motor enclosure. The magnets on the switchmay be located on the shield but opposite the external side of same. Inother words, the shield is sandwiched between the switch's lever arm andthe actual magnets. This means the magnets will face the motor enclosurewhile the lever arm faces the exterior environment of the pump assembly.

In a further illustrative embodiment, the sensor is configured toactivate the motor only upon detecting a magnetic field havingparticular characteristics. For example, the internal sensor must detecta magnetic field having a predetermined strength and alignment in orderfor the sensor to initiate activating the motor. The shield extendslaterally or transverse from the magnet(s) so the magnet(s) are uniquelypositioned and oriented to produce the requisite strength and (inconjunction with movement by the lever) predetermined alignment tosignal to the sensor to either activate or deactivate the pump motor. Itis appreciated that in other embodiments, such magnetic switching may beused to activate other internal components within the motor enclosure.

A perspective exploded detail view of components of fluid transfer pump2 is shown in FIG. 7. Depicted are motor enclosure 4, motor controllercircuit board 82, and switch mechanism assembly 8. Within cavity 52 ofenclosure 4 is motor stator 80 along with internal magnetic sensor 84.It is appreciated that motor controller circuit board 82 is fitted intocavity 52 of motor enclosure 4 as previously discussed. Shown as part ofswitch mechanism assembly 8 is illustratively a pair of magnets 86 and88 to create the magnetic field to be detected by internal magneticsensor 84. In this illustrative embodiment, two magnets are used so asto create a more complex magnetic field that is more difficult to mimic.It is appreciated, however, that a single magnet or other magneticschemes may be employed. Such, alternatives serve the same principle asdefining a magnetic field having a particular characteristic orcharacteristics that must be detected by magnetic sensor 84 in order toactivate or deactivate any component—particularly the motor—in motorenclosure 4.

Further, depicted herein, is how magnets extend from shield 90. Havingmagnets 86 and 88 extend from magnet 90 helps particularize thepositioning of the magnets relative to the sensor 84 inside motorenclosure 4. This further helps ensure the magnetic field generated bythe magnets to ensure only magnets in that particular location willproduce the strength needed to be read by the sensor 84. In addition,shield 90 extends beyond the periphery of magnet casing 89, and, thus,magnets 86 and 88 to serve as shielding so either intentional orincidental magnetic fields from the outside environment will notinterfere with the magnetic field intending to activate sensor 84.

A top downward looking cross-sectional view of a portion of fluidtransfer pump assembly 2 is shown in FIG. 8. This view depicts motorenclosure 4 with motor stator 80 shown housed within cavity 52. Anotheraspect of motor enclosure 4 is switch recess 92 configured to receive aportion of switch mechanism assembly 8. In particular, switch recess 92receives magnet casing 89 that holds magnets 86 and 88. A counter sink94 is illustratively formed on the periphery of switch recess 92 and isconfigured to receive shield 90 from switch mechanism assembly 8. It isevident from this view how magnets 86 and 88 may be contained in cavity92 while being shrouded by shield 90. It should be appreciated from thisview that cavity 92 and counter sink 94 are formed in the exterior ofmotor enclosure 4. They do not extend in any way into cavity 52. Inother words, switch recess 92 and counter sink 94 are isolated fromcavity 52.

A pivot shaft 96, as part of switch shaft assembly 14, is disposedthrough bore 97 of collar 98 and extends into switch recess 92. Pivotshaft 96 may be secured in bore 97 via fastener 18. Pivot shaft 96 isalso attached to magnet casing 89 in order to pivot magnets 86 and 88(see, also, FIGS. 7 and 9) to move same between activation anddeactivation positions.

Side cross-sectional views of motor enclosure 4 are shown in FIGS. 9Aand 9B. These views depict how magnet casing 89 may be pivoted by pivotshaft 96 in order to move magnets 86 and 88 to create the differentcharacteristics of the magnetic field. Again, it is the differentcharacteristics of the magnetic field that indicate to sensor 84 (see,also, FIG. 7) whether the motor should be activated or deactivated. Itis appreciated from these views how the spacing between magnets 86 and88, as well as their positioning in proximity (see, also, FIGS. 7 and8), create a unique magnetic field characteristic for sensor 84 todetect. Lastly, motor controller circuit board 82 is also shown in thisview.

Although the present disclosure has been described with reference toparticular means, materials and embodiments, from the foregoingdescription, one skilled in the art can easily ascertain the essentialcharacteristics of the invention and various changes and modificationsmay be made to adapt the various uses and characteristics withoutdeparting from the spirit and scope of the invention.

What is claimed is:
 1. A fluid transfer pump assembly comprising: amotor enclosure assembly that forms a motor cavity; wherein the motorenclosure includes a flame path composed of a pathway formed by twofacing surfaces of the motor enclosure; wherein the pathway formed bythe two facing surfaces of the motor enclosure extend from an interiorjoint to an exterior joint; wherein the interior joint faces the motorcavity and the exterior joint faces exterior of the motor enclosureassembly; wherein the motor cavity includes a motor controller thatsupplies power to a motor having a rotor and a stator; wherein thestator includes a plurality of pole pairs of wire windings that cancreate a moving electromagnetic force to rotate the rotor; wherein themotor controller, upon receiving signals of a condition of the fluidtransfer pump assembly, directs current to at least one pole pair ofwire windings on the stator at a voltage that does not cause the motorto rotate, and instead causes the at least one pole pair of wirewindings to vibrate to generate a feedback signal.
 2. The fluid transferpump assembly of claim 1, wherein the feedback signal is a statusfeedback signal.
 3. The fluid transfer pump assembly of claim 2, whereinthe status feedback signal is at least one tone to convey at least oneoperating condition of fluid transfer pump assembly.
 4. The fluidtransfer pump assembly of claim 2, wherein the status feedback signal isa plurality of status feedback signals, wherein the at least oneoperating condition of the fluid transfer pump assembly is a pluralityof operating conditions of the fluid transfer pump assembly, whereineach one of the plurality of status feedback signals is indicative ofeach one of the plurality of operating conditions of fluid transfer pumpassembly such that the each one of the plurality of status feedbacksignals for the each one of the plurality of operating conditions is apredetermined signal.
 5. The fluid transfer pump assembly of claim 3,wherein the at least one operating condition of fluid transfer pumpassembly is a plurality of operating conditions of the fluid transferpump assembly, wherein the status feedback signal indicative of each oneof the plurality of operating conditions of the fluid transfer pumpassembly is a predetermined status feedback signal selected from thegroup consisting of the at least one tone and a plurality of tones. 6.The fluid transfer pump assembly of claim 1, wherein the feedback signalis at a frequency that is selected from the group consisting of at leastat least one of audible and imperceptible to a human ear.
 7. The fluidtransfer pump assembly of claim 1, wherein the feedback signal is at afrequency detectable by a microphone to be processed by a deviceselected from the group consisting at least one of a computer and asmart phone.
 8. The fluid transfer pump assembly of claim 1, wherein achange of current distributed to the at least one pole pair of wirewindings changes the feedback signal to that associated with thecondition of the fluid transfer pump assembly.
 9. The fluid transferpump assembly of claim 1, wherein the condition of the fluid transferpump assembly is a detected condition selected from the group consistingat least one of an over voltage, under voltage, high temperature,application fault, and battery fault.
 10. The fluid transfer pumpassembly of claim 1, wherein the fluid transfer pump assembly does notinclude an indictor selected from the group consisting of light andspeaker to act as a feedback indicator.
 11. The fluid transfer pumpassembly of claim 1, wherein the at least one pole pair of wire windingsof the stator of the motor vibrates to generate the feedback signal. 12.The fluid transfer pump assembly of claim 1, wherein the at least onepole pair of wire windings on the stator is a plurality of pairs ofwindings that vibrate to generate a feedback signal.
 13. The fluidtransfer pump assembly of claim 1, wherein the feedback signal is a toneor a sequence of tones.
 14. The fluid transfer pump assembly of claim 1,wherein the condition of the fluid transfer pump assembly is selectedfrom the group consisting of at least one of an application fault andhardware fault.
 15. A fluid transfer pump assembly comprising: a motorenclosure assembly that forms a cavity sized to receive a motor; whereinthe motor enclosure includes a flame path composed of a pathway formedby two facing surfaces of the motor enclosure; wherein the pathwayextends from an interior joint to an exterior joint; wherein the cavityincludes a controller that supplies power to a motor having a rotor anda stator; wherein the stator includes a plurality of pole pairs of wirewindings; wherein the motor controller directs current to at least onepole pair of wire windings on the stator at a voltage that causes the atleast one pole pair of wire windings to vibrate to generate a statusfeedback signal.
 16. The fluid transfer pump assembly of claim 15,wherein the status feedback signal is at least one tone to convey atleast one operating condition of fluid transfer pump assembly.
 17. Thefluid transfer pump assembly of claim 16, wherein the at least oneoperating condition of fluid transfer pump assembly is a plurality ofoperating conditions of the fluid transfer pump assembly, wherein thestatus feedback signal indicative of each one of the plurality ofoperating conditions of fluid transfer pump assembly is a predeterminedstatus feedback signal selected from the group consisting of the atleast one tone or a plurality of tones.
 18. The fluid transfer pumpassembly of claim 15, wherein the status feedback signal is at afrequency that is selected from the group consisting of at least one ofaudible and imperceptible to a human ear.
 19. A fluid transfer pumpassembly comprising: a motor enclosure assembly that forms a cavitysized to receive a motor; wherein the motor enclosure includes a flamepath composed of a pathway formed by two facing surfaces of the motorenclosure; and a motor having a rotor and a stator; wherein the cavityincludes a controller; wherein the stator includes a plurality of polepairs of wire windings; wherein the motor controller directs current toat least one pole pair of wire windings on the stator at a voltage thatcauses the at least one pole pair of wire windings to vibrate togenerate a status feedback signal.
 20. The fluid transfer pump assemblyof claim 19, wherein the at least one operating condition of fluidtransfer pump assembly is a plurality of operating conditions of thefluid transfer pump assembly, wherein the status feedback signalindicative of each one of the plurality of operating conditions of fluidtransfer pump assembly is a predetermined status feedback signalselected from the group consisting of the at least one tone or aplurality of tones.